91.205 equipment requirements for Day VFR.

Tom-D

Tom-D

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Tom-D
Do the electronic compasses such as the one in a Dynon flight system, meet the requirements of 91.205 for a "(3) Magnetic direction indicator."?

IOWs do I have to carry a wet compass if I install the Dynon system?
 
What happens when the power goes away? I will bet dollars that a stand alone compass is still required. All the Boeings and Airbuses I have flown with full EFIS systems have had a stand alone compass.
 
Greg Bockelman said:
What happens when the power goes away? I will bet dollars that a stand alone compass is still required. All the Boeings and Airbuses I have flown with full EFIS systems have had a stand alone compass.
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This is why I asked.
part 91 is different than any ops for a airbus, commuter class aircraft. but IFR is different than VFR day requirements.
But Dynon and others say they are fully IFR capable.
Other than 91.205 I can't locate any regulations saying anything about compasses, or which will meet the requirement.
 
If you have an EFIS (like the G1000, G300, Dynon, GRT, etc), you meet the requirement. What happens if it fails (whatever the reason), or your wet compass falls off the panel? Same answer: you get if fixed. If you need to fly somewhere to do so, you need a Ferry Permit.
If the plane is IFR, it is prudent (but not required - so Greg, pay up :)) to have backup. I have an EFIS and a compass in my RV.
I instruct in a SkyCatcher and a G1000 172. If the G300 in the SkyCatcher fails, you look out the window (it is a VFR only airplane). The IFR 172 has a wet compass (and backup 'steam guage' instruments) to back up the G1000.
 
the answer is you must have a magnetic direction indicator. now, for a type certified aircraft you know the answer, it must meet the requirements of the type certificate if required, be faa approved ect. ect. ect. for homebuilt, it must be a magnetic direction indicator. period. wet,electronic,what ever you want. buy a TSO unit or one at the walmart auto isle, your call, the only real requirement is that it be attached to the aircraft. the compass on you key chain is not going to pass a DER's inspection.

bob
 
IMO Yes. However, some DARs and FSDOs interpret it in their own way. For example, I know of one FSDO inspector who insists on a wet compass even though the FAA says a magnetometer/EFIS setup is legal.

Interestingly enough, if you have standard OPLIM wording then 91.205(b), [FONT=Arial, sans-serif]Visual-flight rules (day), [/FONT]does not apply to E-AB aircraft for day VFR ops which means there's technically zero instrument requirements for day-VFR -- but good luck getting a DAR or FSDO to sign off on a plane with no instruments. However, with standard OPLIM wording, 91.205(b) does apply if you want to fly at night or under IFR operations.
 
mikeinbama said:
(3) Magnetic direction indicator. My guess is you gotta have the Mag compass.
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I read "Magnetic" as the parameter being sensed, not the type of instrument. In any case, the Dynon senses and interprets the earth's magnetic field just as surely as a magnetic compass.

Had the FAA wanted redundancy or a non-electronic method, they would have (or should have) said so.
 
We do not have a magnetic compass, as in a whiskey compass, but we have a backup HSI which gets it's information from a magnetometer, and is powered by a standby battery.
 
unsafervguy said:
the answer is you must have a magnetic direction indicator. now, for a type certified aircraft you know the answer, it must meet the requirements of the type certificate if required, be faa approved ect. ect. ect. for homebuilt, it must be a magnetic direction indicator. period. wet,electronic,what ever you want. buy a TSO unit or one at the walmart auto isle, your call, the only real requirement is that it be attached to the aircraft. the compass on you key chain is not going to pass a DER's inspection.

bob
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For an example of a type-certified aircraft, I just checked the equipment list in a 172N manual, and the compass is marked as required. I assume that means that substituting a different type of magnetic direction indicator would require some kind of official paperwork.
 
Everskyward said:
We do not have a magnetic compass, as in a whiskey compass, but we have a backup HSI which gets it's information from a magnetometer, and is powered by a standby battery.
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Same here - no compass. I have a magetometer feeding a 2-screen EFIS plus 3 separate GPS's (5 if I count my tablet and iPhone).
 
tsts4 said:
IMO Yes. However, some DARs and FSDOs interpret it in their own way. For example, I know of one FSDO inspector who insists on a wet compass even though the FAA says a magnetometer/EFIS setup is legal.

Interestingly enough, if you have standard OPLIM wording then 91.205(b), [FONT=Arial, sans-serif]Visual-flight rules (day), [/FONT]does not apply to E-AB aircraft for day VFR ops which means there's technically zero instrument requirements for day-VFR -- but good luck getting a DAR or FSDO to sign off on a plane with no instruments. However, with standard OPLIM wording, 91.205(b) does apply if you want to fly at night or under IFR operations.
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To fly under FAR 91 rules, you must have the required equipment. Just like you must comply with weather rules, safe distance rules and all that.
You can't pick and choose which part of the rule you wish to comply with.
 
Tom-D said:
To fly under FAR 91 rules, you must have the required equipment. Just like you must comply with weather rules, safe distance rules and all that.
You can't pick and choose which part of the rule you wish to comply with.
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Incorrect. Re-read 91.205. The para title and sub-para (a) states that the equipment requirements apply to Standard category airworthiness certificated aircraft. E-AB's are Special airworthiness certificated aircraft. Therefore 91.205 does not apply for E-AB day VFR operations unless the aircraft's OPLIMs specifically require it to which with standard OPLIM wording out of 8130.2H they won't. With standard OPLIM wording, 91.205 only becomes applicable for night and IFR operations and then the whole Paragraph becomes applicable to include the day VFR requirements in sub-para (b).

Give me a FAR ref or any other FAA doc that proves me wrong.
 
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tsts4 said:
Incorrect. Re-read 91.205. The para title and sub-para (a) states that the equipment requirements apply to Standard category airworthiness certificated aircraft. E-AB's are Special airworthiness certificated aircraft. Therefore 91.205 does not apply for E-AB day VFR operations unless the aircraft's OPLIMs specifically require it to which with standard OPLIM wording out of 8130.2H they won't. With standard OPLIM wording, 91.205 only becomes applicable for night and IFR operations and then the whole Paragraph becomes applicable to include the day VFR requirements in sub-para (b).

Give me a FAR ref or any other FAA doc that proves me wrong.
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You bring up a good point, Todd. You are correct, but you might want to check FAA Order 8130.2H which says that for special airworthiness certificates, the FAA may impose conditions such as...

Depending on the intended operation, the applicable reference would be § 91.205(b) for VFR (day); § 91.205(c) for VFR (night); and § 91.205(d) for instrument flight rules (IFR). Operators should be alerted that there are specific requirements under part 91 for maintenance and inspection of the various aircraft instruments, and that those requirements are applicable for these aircraft if the instruments are installed, for example, §§ 91.173 through 91.187, 91.215, 91.217, 91.219, 91.411, 91.413, etc.​

So I guess the question is, are you aware of any e-AB special airworthiness certificates that do not include 91.205 equipment for the applicable type of 0peration within the NAS?
 
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I've got the flux gate driving my HSI. I still have the whiskey compass primarily as there's no reason to take down the "dashboard icon" as Beldar would say.
 
tsts4 said:
Incorrect. Re-read 91.205. The para title and sub-para (a) states that the equipment requirements apply to Standard category airworthiness certificated aircraft. E-AB's are Special airworthiness certificated aircraft. Therefore 91.205 does not apply for E-AB day VFR operations unless the aircraft's OPLIMs specifically require it to which with standard OPLIM wording out of 8130.2H they won't. With standard OPLIM wording, 91.205 only becomes applicable for night and IFR operations and then the whole Paragraph becomes applicable to include the day VFR requirements in sub-para (b).

Give me a FAR ref or any other FAA doc that proves me wrong.
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Good find,, I'll buy that interpretation.
 
Tom-D said:
Good find,, I'll buy that interpretation.
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The Chief Counsel buys it also. 2009 Rourke Interpretation. But beware of the conditions of a special airworthiness certificate that may well incorporate them anyway. Whether "no, it doesn't apply" has a practical effect or not in what you are looking at is only something that can be determined when looking at a specific situation.
 
midlifeflyer said:
You bring up a good point, Todd. You are correct, but you might want to check FAA Order 8130.2H which says that for special airworthiness certificates, the FAA may impose conditions such as...

Depending on the intended operation, the applicable reference would be § 91.205(b) for VFR (day); § 91.205(c) for VFR (night); and § 91.205(d) for instrument flight rules (IFR). Operators should be alerted that there are specific requirements under part 91 for maintenance and inspection of the various aircraft instruments, and that those requirements are applicable for these aircraft if the instruments are installed, for example, §§ 91.173 through 91.187, 91.215, 91.217, 91.219, 91.411, 91.413, etc.​

So I guess the question is, are you aware of any e-AB special airworthiness certificates that do not include 91.205 equipment for the applicable type of 0peration within the NAS?
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yes they can and they have to be spelled out in your operating limitations, they are not on mine.

bob
 
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